The A-4 uses the same super responsive and lightweight highback we've had in the past. The One-Piece Ankle Strap offers performance and comfort without the extra bulk and weight. The cored nylon highback is designed for responsiveness without the additional weight. The A-Series Aluminum Chassis provides the reactive flex and power transfer of aluminum with less rigidity than previous designs. The canted footbed aligns your joints with a 2.5 degree angle while providing more leverage over the tip and tail of your board. If you are on a tight budget, but demand lightweight all mountain performance, this is the binding for you.